New Technologies in Low-Invasive Surgery of Skull Base Tumors

A.N. Shkarubo

Burdenko Research Institute of Neurosurgery, Russian Academy of Medical Science, Moscow, Russia

 

Introduction. Different transcranial approaches, including widened transcranial-transfacial ones, are used for removal of tumors of skull base anterior segments. Extracranial approaches (transsphenoidal and/or transoral) with use of natural anatomic cavities may be regarded as minimum-invasive in such pathology. A depth and narrowness of a wound are ensured by introduction of intraoperative endoscopic control, which is a new prospective technology in neurosurgery, as well as by simultaneous use of transsphenoidal and transoral approaches.

Materials and Methods. We operated 137 patients, aged 8-68 (a median value of 34 years). A transsphenoidal approach and intraoperative endoscopic control (rigid and fiber endoscopes) were used in 117 cases. There were operations for pituitary adenomas (5 cases with endosellar and 89 cases with endo-extrasellar localization), endo-extrasellar craniopharyngioma (12), skull base chordoma (6) other skull base tumors (5). A transoral approach was performed in 19 cases with chordomas. Patients of this group with skull base chordomas and instability of the craniovertebral junction (2 cases) were subject to one-stage occipitospondylodesis and subsequent transoral removal of tumor. There were 4 cases with spread skull base chordomas, in whom we used a combined approach (transnasal and transoral); 1 patient with metastasis into C2 body underwent one-stage occipitospondylodesis with a metal device and transoral removal of tumor. There was no need of endoscopic control in transoral and combined approaches; it was caused by peculiarities of a tumor spread. Instruments, devices and methods of surgical treatment, patented by us, were used in all the cases.

We received the gold medal and special diploma of the IV Moscow International Salon of Innovations and Investments (Moscow, All-Russia Exhibition Center, February 25-28, 2004) and the Grant of the RF Government for the START Contest Program (N 292- 1-113, 004). Sealing and plasty of the skull base were performed in 22 cases aster tumor removal. It was done with the help of original methods, patented by us, which permitted to prevent postoperative liquorrhea.

Results and Discussion. Indications for transsphenoidal, transoral approaches and their combinations (one-stage use) were determined. Endoscopic technique, used in transsphenoidal approach, allowed:

Transoral and combined (transsphenoidal and transoral) approaches made it possible to perform radical removal (total and subtotal) in 47.3% (9 out of 19) of patients. Regression of clinical symptoms was watched in the majority of cases. Intraoperative liquorrhea was observed in 2 cases; there was no postoperative liquorrhea. Repeated operations were made in 1.5-2 years in 4 patients. One-stage occipitospondylodesis with subsequent transoral removal of tumor turned out to be justified. It allowed to improve treatment quality and to reduce its cost.

Conclusion. New technologies in minimum-invasive surgery of skull base tumors permit to optimize surgical technique, to improve treatment quality, to reduce a number of intra- and postoperative complications, to widen indications for use of low-traumatic approaches in surgery of skull base tumors. Further research in this field and improvement of surgical technique and methods of surgical treatment are necessary.